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/*! \file
  \brief Functor performing reduction operations used by epilogues.
*/

#pragma once

#include "cutlass/cutlass.h"
#include "cutlass/numeric_types.h"
#include "cutlass/array.h"
#include "cutlass/functional.h"
#include "cutlass/numeric_conversion.h"

/////////////////////////////////////////////////////////////////////////////////////////////////

namespace cutlass {
namespace epilogue {
namespace thread {

/////////////////////////////////////////////////////////////////////////////////////////////////

/// Applies a reduction sum to an array of elements.
///
///
template <typename Element_,  ///< Data type used to load and store tensors
          int Count           ///< Number of elements computed per operation
          >
class ReductionOpPlus {
public:
    using Element = Element_;
    static int const kCount = Count;

    using Fragment = Array<Element, kCount>;
    using Operator = plus<Fragment>;

    /// Host-constructable parameters structure
    struct Params {};

private:
    /// reduction operator
    Operator operator_;

public:
    /// Constructs the function object, possibly loading from pointers in host
    /// memory
    CUTLASS_HOST_DEVICE
    ReductionOpPlus(Params const& params) {}

    /// Computes Compute =>
    CUTLASS_HOST_DEVICE
    Fragment operator()(Fragment const& lhs, Fragment const& rhs) const {
        return operator_(lhs, rhs);
    }
};

/////////////////////////////////////////////////////////////////////////////////////////////////

}  // namespace thread
}  // namespace epilogue
}  // namespace cutlass
